Fuel injection pump



Jan, 21, 1947. L J, GARDA, 2,414,518

FUEL INJECTION Pml mea uw. '12, 1942 ls sneetssneet 1 Jam 21, 1947' I l.. J.' GARDAY V 2,414,518

FUEL INJECTION PUMP Filed Dec. 12, 1942 3 Sheets-Sheet V2.

cations may be made by v cams. a cam lobe for iluld displacement and is retracted pump pistons Patented Jam Zi, E94? UNITEDA STATES PATENT oFFIcEj FUEL INJEc'rroig rum Louis J. Garday,

Glenview, lll., asslgnor to Aircraft & Diesel Equipment Corporation, Chicago,

Ill., a corporation of Delaware application December 12, 1942, serial No.

-18 Claims.

This invention trols therefor, and particularly to pump and conand the like.

The invention is especially adapted for use in I connection with multiple-cylinder engines of various types, and it will be apparent that modifiart to adapt the invention for use in connection with any suitable type of engine without departing from the spirit of the invention.

Any required number of engine cylinders and associated pumps may be used. However, the

specic structure shown in the drawings was designed for use on a fourteen-cylinder Diesel engine or the like. Itis an object of the invention to provide an interchangeable'precalibrated pumping unit that permits quick removal -and replacement of damaged units; that permits individual setting of the unitsto suitable calibration marks, and in which a single operating control regulates thedischarge quantity of all of the pump units with the consequent uniform fuel injection to each cylinder.

In the embodiment shown, a radially positioned in its respective casing in position to be individually set to predetermined calibration marks by suitable means provided for this purpose and to automatically be successively operated by suitable Each pump piston is axially movable by by means of a compression spring. All of the are to predetermine pump; l It is another object of the invention to provide a single controlling device for the simultaneous control of the pump pistons wherein the control mechanism includes yieldable means associated the discharge flow 'from each with each pump and constructed to permit rotarymovement'in one or both directions oi some of the pistonseven though one or more of the pistons abnormally resists rotation. y'I'his is an important feature for the reason that an individual piston may sometimes become damaged,

or may stick in such a manner that it cannot be moved to the desired position. With the ordinary apparatus for rotating the fuel pump pistonsof this type, in the event a piston sticks for anyreason, none of the fuel pumps can properly be rotated, and therefore the remaining cylinders persons skilled in the (ci. 10a-4i) of the engine cannot be throttled down or othersimultaneously rotarily settable wiseV controlled which may result in serious damage to the engine.`

It is also an object oi' the invention tol provide an improved pump construction whereby the en-4 apparent from the dise A Fig. 1 is a front elevationpartially i-n section plurality of an engine frame; Y

Fig. 2 is a sectional view through a plurality of pumps and is taken on corresponding to line 2-2 of Fig. 1; t

Fig. 3 is a transverse sectional view takenv on operating the pumps; Fig. 4 is a detail sectional view taken on agllne corresponding to line 4-4 of Fig. l; y Fig. 5 is a side elevation of one of the; pump units completely assembled and ready for mountposes of illustration;

Fig. 6 is a bottom ment shown in Fig. 5;

.'Fig. 7 'is an axial sectional view through the pump unit assembly and is taken on a line corresponding to line 'l-'I of Fig. 5;

Fig. 8 is a detail sectional view through the piston stem and through the piston-aligning view of' the pumpembodia line substantially porting washer shown in Figs. and 6;

Fig. l1 is a sectional view similar to Fig. 3,

` but illustrates a slightly modified form of pump control mechanism;

Fig. l2 is a transverse sectional view taken on a line substantially corresponding to line I'Z-lZ of Fig. 11; and

f Fig. 13 is a fragmentary perspective view of certain of the cooperating elements shown in Fig. 1l. l

Referring to the drawings in detail, the ern.- bodiment illustrated in` Figs. 1 to 4, inclusive, comprises an annular pump frame I mounted on or forming a part of the frame of a suitable internal combustion engine. frame I is, in the present embodiment, concentric with the axis of .a fuel pump cam which has several lobes suitable for operating the pumps in a' manner which will be described later.

The annular pump frame I Acomprises a plurality of radially disposed pump casings 2. Each pump casing 2 is provided` with a radial bore therethrough to receive a pump unit 3, which latter comprises a body 4 (Fig. '1). ,The body 4 supports all of the various elements of the pump unit and is provided at its upper end with a flange 5 whereby the unit may be secured in position in any one of the casings 2 by means of bolts 6 inserted through the holes 1 in the flange (Fig. 6) and secured in the casing. A suitable gasket 8 may beprovided fori sealing the upper end of the pump unit against the end of the casing. y

Each pump body 4 is provided with Aan an nular groove 9 and, when the pump units are inserted in their respective casings, all4 of the grooves 9Jcommunicate with connecting fuel supply passageways III extending between the casings, so that all of the pumps may continuously be supplied with liquid fuel from a supply in the usual manner.

As previously stated, the present embodiment is designed for use in connection with a 'Iourteencylinder engineA and.' therefore fourteen pump casings and pump units are provided. The pump The annular pump nection is effectively sealed by meanspf a suitable packing I8. The valve I8 is normally held in closed position by means of a compression spring i9, and a valve stop 20 Ais. provided Ato limit the movement of the valve I6. The nipple I1 is provided with an outlet passage 2I and the nipple is externally threaded as shown-and connected to a suitableconduit, not shown, leadi ing to the associated engine cylinder.

The pump cylinder i3 is provided adjacent its upper end with an inlet port 22 which communicates with the annular fuel supply groove 9 through an inlet passage 23.A The cylinder is also provided with an overflow passage 24 communicating with the annular groove 9 through a passage 25. These ports are preferably oppositely disposed, as shown, with the overflow passage slightly below the transverse plane of the inlet port.

A piston 26 is mounted for longitudinal movement in the cylinder I3 and is provided adjacent its upper end with an annular groove 21, which groove communicates with the pressure space in the upper end of the cylinder through a longitudinal peripheral groove 28. The groove 21 has an upper inclined or helical yedge 29 intersecting the vertical groove 28 and is so related to the overflow ,port 24 that the effective delivery stroke of the piston may be regulated as required by rotarily positioning the piston in the cylinder to thereby vary the point in the delivery Y stroke in which the overflow port 24 is placed casings and units therein are arranged radiallyv in two adjacent annular series withvseven pumps in.each series. The unitsv in each row orv series are, equally spaced radially and are 'staggered' with respect to the units in the adjacent row,

so that all of the units are equally spaced one from the other and axially positioned on radial lines around a cam shaft.

',The vbody 4 of each unitV 3 is provided with a sealing'ring vor other suitable packing II below the groove 9, so that the fuel passageway is effectively sealed .when the unit is inserted in the casing. The body 4 is provided with an axial ,bore I2 in which is mounted a pump cylinder I3, which latter is provided with a shoulder I4 for engaging a complementary shoulder on the body 4. The pump cylinder I3 extends materially bclow the-bottom of the` body 4 and is closed at its upper end by means of a bushing I5 (Fig. 1) having an axial valve I6 slidably mounted therein. The bushing I5is retained and sealed in position by means of la packing nipple I1 threaded into the body 4 and the conin communication with the pressure chamber through the grooves 21 and 28. By this arrangement, the pump displacement through the outlet passage 2I leading to the engine cylinder begins as soon as the piston, on'its displacement stroke, covers the ports 22 and 24, and the fuel delivery stops as soon as-the inclined portion of the annular groove 21 `communicates with the overflow port 24 to thereby relieve the pressure in the pump cylinder.

As previously stated, the pump cylinder I3 extends a material distance beyond the lower end of the body 4, and the piston 26 is provided with au elongated `stem 30 which stem extends below the end of the cylinder I3.

A gear 3l is mounted lfor rotation on the protruding end of-the cylinder I3 and snugly .adjacent the body 4. Thegear 3l is provided with an elongated skirt 32 having a `longitudinal slot 33 therein as shown particularly in Fig. 5.,

The piston stem 30 is provided with a collar 34,

which collar is secured against rotation andv against longitudinal movement by means of a Woodrud key 35 (Fig. 7). The key 35 prevents relative rotary .movement between the piston stem 30 and the collar 34, and a pin 36 is trans'- verselyl inserted through the collar and the Woodruff key, as shown, so that the elements are securely locked together to prevent 'relative movement in any direction.

By the above described arrangement .of the key'35 and the transverse pin 36, relative to the stem 30 and the collar 34, the collar may be accurately positioned on the stem even though this stem is hardened. Drilling .of the stem after hardening, or hardening the stem after drilling the hole, is impractical due to the accuracy which must be maintained with respect to the final locaassociated with the pin. If the collar also is hardened a transverse hole may be formed there' in prior to hardening, and the key only is drilled sleeve 3d. rI'liis sleeve is pose one side of the gear in the usual fashion, and the i shown best in Fig. 9, and

the circumference to andere Y A suitable spring 26 is providedas shown, and is adapted to surround the-stem 3i)- of thepiston, the skirt 32 of the gear 3i, and the cooperating arm 3l. In order to retain all of the elements of the precalibrated unit in assembled site ends of the spring d3 are squared and ground gear cover or sleeve 38 is provided adjacent its lower end with an which is spaced from a shoulder 38a` (Fig. 7) to provide a groove 32a. When the upper end of the spring 6 3 is inserted into the sleeve 38 and rotated, a portion of the ilrst turn or round on the spring will be threaded into the groove 62a and may be wedged `0r tight-- ened between the shoulder 38a andthe lip 42 so as rmly to secure the spring to the sleeve 38 l without interfering with the compression and extension of the spring.

Similarly, a slotted washer45, which engages an enlarged head or flange d4 on the stem 30 of the piston, is provided with an outturned lip d6 (Figs. 7 and 10) extending partially about which the first turn or round on the lower end of the spring may be threaded and tightened. Thus all of the cooperating and relatively mov-v able elements of the unit are retained in assembled relation'with the spring 43 relaxed and the piston in its retracted position, the arm 437 being of sumcient length to maintain its er1-- gagement in the slot 33 throughout the normal range of extension of the spring 43.

The gear 3i and brated by means of a vertical slot 41 lin the face oi" one of` the gear teeth and a calibration line 88 on the pump body 4 (Fig. 5). The elements 43 for operating the piston v relation, the oppo'- body 4 are relatively caliare so constructed and the calibration lines are 1 so related thereto that, when these calibration `lines are in alignment, the pump will deliver a predetermined output; also, rotary movement of the gear in either direction will correspondingly vary the pump output.

One of the pump casingslV is shown in section in Fig. 1 with the pump unit installed therein. The casing 2 is provided at its lower end with a bushing 49 in which is slidably mounted a tappet 50 having at its lower end a cam fllowercomprising a roller 5i, The lower end of the pump piston is pressed against this follower by. the

spring 43 so as to retain the follower in contact with its respective cam surface.

In order to operate the two units, a cam drum is provided comprising a cam 52 for operating the inner series of pumps and This predetermined output, a con- This` control mechanism comprises a ring or disc-like member 5l -on which is pivoted Aatff/'a series,l of control elements or bell cranks @ya is secured on a longitudinally slidable rack 64 in mesh with the pump gear 3|. One side of the pump gear is exposed through an opening in the casing 2', andthis of a plate 65, the rack 64,

either direction. The stop screws 6| may all be adjusted, to accurately set the control elements or bell cranks The bell crank springs 60 and the-bell cranks are mounted relative to the ring 51, so that when the ring is rotated in the direction of the arrow occur between the associated bell crank and the control ring. By this construction a ydefective or stuck pump will not interfere with the proper is rotatably mounted on a bearing 66 and in axial alignment with lthe pump 53. rality of outer beveled gear segments 6l', each of which is adapted to control an associated one o fV the outer series of pumps .through a suitable series of pump either manually or by suitable.

lost motion mechanism. V'l'he ring 51a is also provided with a plurality of innerv beveled gear segments 68. which latter are similar to the gear segments 61, but are positioned to control the inner series of pump units through similar lost. motion mechanisms.

. The lost motion mechanism for each pump unit comprises a pinion segment 69 having a hub 10 rotatably mounted in a vertical bore 1| inthe pump casing and parallel with the-axis of the pump. A lost motion element 12 is also rotatably mounted in the bore 1l and is secured to .the segment pinion Sil-by means of a bolt or shaft 13, so as to permit relative rotary movement of the control elements to provide lost4 motion therebetween iny one direction while at the same time retaining them in assembled relation. i

A gear segment 14 is secured for' rotary movement on the upper end of the element 12 by means of the bolt 13 .and a suitable washer 15. This gear segment 14 is in mesh with the pump unit gear 3l as illustrated in Fig. 12. The gear segment 14 may be rotarily adjusted with respect to the lost motion element 12 by means of set screws 16 which engage shoulders'11 on the member 12.

The lower portion of the element 12 is reduced in diameter and a coiled torsion spring 18 is 'mounted thereon. The upper free end of this spring is bent upwardly andengaged in a slot 19 in the side of the element 12 and adjacent the upper end thereof, and the lower end of the spring is engaged in a slot 80 in the side of the hub of the segment pinion 69. The lower end of the lost lmotion element 12 is cutaway at 8| (Fig. 13) and an upwardly extending lug 82 on the pinion segment 69 is engaged in the slot formed by the cutaway portion 8|. This lug 82 is normally tensioned against one of the shoulders Bia. of the member 12 by means of the spring 1B, so that in case the valve should stick forianyre'ason, a lost motion in one direction is provided between the4 control ring 51a and the pump in substantially the same manner as in the embodiment previously described.

As previously stated, each pump is precalibrated and marked by means of the calibration slot 41 and line 48.; also, the control devices may be adjusted for uniform operation of the pumps by means of the set screws 18 for adjusting the gear segment 14 to conform with thepump calibration. l

While I have shown particular embodiments of my invention, it will bev understood, of course,

that I do not wishl to be limited thereto since many modifications may be made, and I, therefore, contemplate by .the appended claims to cover Vany such modificationsy as fall within the true spirit and scope of my invention.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. Ina fuel injection pump of the type having a plurality of cooperating cylinders and pistons, the pistons being axiallyv displaceable to provide a pumping effect fand being rotatable tojcontrol the pumping effect, the combination of individual means associated with each cylinder and operable to rotate the corresponding piston, a common movable operating element, and individual connecting means between said element and each of said individual means for normally effecting si-A multaneous rotation of all of said pistons upon movement of said element, each of said connecting means including yieldable means for permit- 15 ting movement of said element to rotate some ofv said pistons even though one or more ofsaid pistons abnormally resist rotation.

2. In a fuel injection pump of the type having a plurality of cooperating cylinders and pistons, the pistons being axially displaceable to provide a pumping effect and being rotatable to control the- -p'umping eiect. vthe combination of individual means associated with each cylinder-and operable to rotate the corresponding piston, -a common' movable operating element, connecting means between said element and each of said individual means for normally effecting simultaneous rotation of all of said pistons upon movement of said element, said connecting-means including yieldable means for permitting movement of said element to rotate some of said pistons even though ,one or more of said'- pistons abnormally resist rotation, and means for individually adjusting each of said connecting means initially-to rotarily positionl said piston relative to said operating element.

3. In a fuel injection pump of the type having a plurality of cooperating cylinders and pistons,

I the pistons being axially displaceable to provide a pumping effect and being rotatable to control the pumping effect, the combination of individual means associated with each cylinder and operable to rotate the corresponding piston, acommon movable operating element, connecting means between said element and each of said individual means fornormally effecting simultaneous rota-' tion of all'of said pistons upon movement of said element, said connecting means including lost motion connections for positively driving said individualmeans in one direction and yieldable means normally preventing relative movement in said lost motion 'connections for driving said individual means in the opposite direction, said yieldable means and lost motion connections permitting movement of said element to drive some of said pistons in said opposite direction even though others thereof abnormally resist rotation.

4. In a fuel injection pump of the type having a plurality of cooperating cylinders and pistons, the-pistons being axially displaceable to provide apumping effect and being rotatable to control the pumping effect, the combination of individual means associated with each cylinder and operable to rotate 'the corresponding piston, a commonof said pistons -in said opposite, direction evenf though others thereof abnormally resist rotation, and means forindividually adjusting said lost motion connections initially to rot'arily position said pistons in predetermined operative relationship to said operating element.

5. In a fuel injection pump of the type having cooperating cylinders and pistons, the pistons being axially displaceable to provide a pumping effect andbeing rotatable to control the pumping effect, the combination of individual means associated with each cylinder and operable to rotate the corresponding piston, a common movable opin engagement with thereof, a key having a erating element. a plurality Vof arms pivotally mounted on said operating element and respectivelyl connected to said individual means, spring tending to rotate each of said arms about its pivot, and abutment gaging said element to limit the pivotal movement of said arms by said spring means, said spring means normally retaining said abutment means said element whereby said arms effect rotation of said pistons inaccordance with movements of said member in either direction, said spring means being yieldable to permit pivotal movement of the associated arm-When a corresponding piston abnormally resists rotation, whereby said element may be moved in one direction to rotate the remaining pistons even though said corresponding piston is not rotatable.

6. In a fuel injection pump of the type having cooperating cylinders and pistons, the pistons being axially displaceable to provide a pumping eilect and being rotatable to control the pumping effect, the combination of individual means associated with each cylinder and operable to rotate the corresponding piston, a common movable operating element, a plurality of larms pivotally mounted on said operating element and respectively connected to said individual means, adjustable abutment means on each of said arms for engaging said element in predetermined adjusted positions of said arms` relative to said elements, and spring means for normally retaining said arms in said adjusted positions whereby movement of said element eilects movement of all of said arms simultaneously to rotate said pistons,

.said spring mean's being yieldable to permit piv- Otal movement of the associated arm from said adjusted position when a corresponding piston abnormally resists rotation.

7. In a fuel injection pump of the type having a cylinder and a hardened piston therein including an extending end portion, said piston being axially displaceable in said cylinder to provide a pumping effect and being rotatable to control said pumping effect, the combination of an operating member for eiecting rotation of said piston including a collar adapted ing end portion of said piston, said portion having an axially extending slot in the external surface portion thereof disposed in said slot and restrained against axial and transverse movement by the end and sidewalls of said slot, said collar having a slot in an internal surface thereof open at one` end for receiving said key when said collar piston, whereby said piston against relative key locks said collar and rotation, and a locking pin i extending transverselythrough said collar and collar against relative axial said key to lock said movement on said piston.

8. In a fuel injection pump of the type having a cylinder and a hardened'piston therein including an extending end portion, said piston being axially displaeeable in said cylinder to provide a pumping effect and being rotatable to control said pumping effect, the combination of an opl erating member for effecting rotation of said piston including a. collar adapted to encircle said extending end portion of said piston, said portion having an axially extending 4slot in the external surface thereof, a key having a portion thereofdisposed in said slot and restrained against axial and transverse movement by the end and'sideV walls of said slot, said collar having a slot in an internal surface thereof open at one end for receiving said key when said collar is axially pressed means n each arm E11- to encircle said extendte 1 i onto said piston, whereby said key locks said collar and piston against relative rotation, said collar and said key having a hole drilled transversely therethrough after assembly on said piston, and a locking pin in said collar and said piston ment.

9. In a fuel injection pump of the type having a cylinder and a hardened piston therein including an extending end portion, said piston being axially displaceable in said cylinder to provide a pumping effect and being rotatable to control said pumping eilect, the combination of an operating member for eiiecting rotation of said piston including a collar adapted to encircle said extending end portion of said piston, said portion the external against relative axial movesaid key when said collar is axially pressed onto said piston, whereby said key locks said collar and piston locking pin exable for pump displacement and rotar-ily adjustable to vary pump displacement, the method of rigidly securing on said piston in precision relation thereto an operating member having :an unhardened collar adapted to encircle said hardened sembling said collar onto said piston with said collar slot receiving said key,

ing said collar and key after assembly to provide a hole therethrough at one side of said pisis axially pressed onto said -l tion to each other.

ton, and inserting a locking pin' into' said hole to lock said piston and collar in precision rela- 11. In a fuel injection pump having a cylinder and a hardened piston therein includingan exonto said piston with 4said collar/slot receiving said key, transversely drilling said key to provide 'a hole through said collarand key at one side oi"V ing a bodyhaving a longitudinal bore, a cylinder in Said bore and having an end projecting outdrilled hole for locking said transversely drill- 11 wardly from said body, a piston having a portion thereof extending Ybeyond the projecting end said cylinder, a sleeve having a longitudinal slot therein, means rotatably mounting said sleeve on the projecting portion of said cylinder, a finger on said piston extending parallel to the axis of said piston in spaced relation thereto gaged Iin said slot to provide a longitudinally slidable connection between said sleeve and said piston, and resilient. means cooperating between the extending end of said piston and said, sleeve to retain all of said elements in assembled relation.

13. In a fuel vinjection pump of the type having a piston axially displaceable in a.cylinder for pump displacement and rotatable to vary displacement, a precalibrated sub-assembly comprising a body -having a longitudinal bore, a cylinder in said bore and having an end projecting outwardly from said body, a piston having a portion thereof extending beyond the projecting end of said cylinder, a sleeve having a longitudinal slot therein, means rotatably mounting said sleeve on the projecting portion of said cylinder. a finger on said piston extending parallel to the axis of said piston in spaced relation thereto and engaged in said slot to provide'a longitudinally slidable connection between said sleeve and said piston, resilient means cooperating between the extending end of saidpiston and said sleeve to retain all of said elements in assembled relation, said finger and slot being proportioned to maintain said slidable connection throughout the entire range of movement of said resilient means.

14. In a fuel injection pump of the type wherein a piston is axially reciprocabie in a c ylinder for pump displacement and rotatable in the cylinder to vary displacement, a'precalibrated sub-assembly comprising a pump body having a longitudinal bore. a fixed cylinder member in said bore and projecting therefrom, -a piston in said cylinder and projecting therefromfa control element rotatable on said projecting cylinder, a longitudinally slidable connection between said pis- 'ton and said control element to maintain radial alignment and prevent relative rotation therebetween, a spring for axially displacing said piston in an outward direction, means securing one end of said spring to said piston, and means on said body for securing the other end /f said spring and said control element in longitudinally fixed relation to said body, said slidable connection maintaining said piston v, and said control element aaginst relative rotation throughout the entire range of extension of said spring whereby said sub-assembly is maintained in properly assembled relation.

15. In a fuel injection pump ofthe type wherein a piston is axially reciprocable in a cylinder for pump displacement and rotatable in thecylinder to vary displacement, a precalibrated subassembly comprising a pump body having a longitudinal bore, a fixed cylinder member in said bore and projecting therefrom, a piston in said cylinder vand projecting therefrom, a control element rotatable on said projecting cylinder, a longitudinally slidable connection between said piston and said control element to maintain radial alignment and prevent relative rotation therebetween, a spring for axially displacing said piston in an outward direction, means securing one (ifL . end of said spring to e element against and enspring and said control elementin longitudinally fixed relation to said housing, said slidable connection maintaining said piston and said control relative rotation throughout the entire range of extension of" said spring whereby said sub-assembly is maintained in properly assembled relation, a calibration mark on an accessible external surface of said control element, and a cooperating calibration mark on said body, said calibration mark being related to predetermine an initial displacement of said pump.

. 16. A precalibrated sub-assembly unit for a fuel injection pump comprising a body adapted to be mounted in a pump casing, said body having a pump cylinder projecting therefrom, a piston axially movable in said cylinder for pump displacement and rotatable to vary said displacement, a

control element rotatably mountedon said projecting cylinder, a longitudinally slidable connection between said piston and said control element to prevent relative rotary movement there- `one end of said spring `mounted in a pump between, a spring foraxially displacing saidv piston in an outward direction, means for securing to said piston, and means carried by said body for securing said control element and the other end of said spring in axially iixed relation to said body, so that all of the elements of said unit are1 eid in assembled relation.

i7. A precalibrated sub-assembly unit for a fuel injection pump comprising a body adaptedto be i casing-said body having a pump cylinder projecting therefrom, a piston axially movable in saidcylinder for pump displacement. and rotatable to vary said displacement, a control element rotatably mounted onM said projecting cylinder, a longitudinally slidable connection between said piston and said control element to prevent relative rotary movement therebetween, a spring for axially displacing said piston in an outward direction, means for securing one end of said spring to said piston, a cup shaped member having the upper end thereof secured to said body for supporting said control element.

in longitudinally fixed relation, said cup shaped member having an aperture in the bottom wall thereof through which said piston and a portion of said control element extends, and means for securing the other end of said spring to said cup shaped member to maintain said sub-assemblyin assembled relation.

18. A precalibrated sub-assembly unit for a fuel injection pumpy comprising a body adapted to be pump cylinder projecting therefrom, a piston axially movable in said cylinder for pump displacementiand rotatable to vary said displacement, a.

control element rotatably mounted on said projecting cylinder and comprising a gear portion having a reduced sleeve port-ion extending therefrom, a longitudinally slidable connection between said piston and said sleevel portion, and a cup shaped member surrounding'said gear portion and secured to said body for supporting said control element, in axially iixed relation to said body. said cup shaped member having an aperture through which said sleeve portion extends.

' V LOUIS J. vGARDAY.

said piston, and means on l said housing for securing the other end of said said body having a l 

